Ceiling grid systems for supporting tile panels, such as acoustical ceiling tiles, are used extensively in both new and remodeled building and room structures. Grid systems typically consist of main-runners and cross-tees, having lateral supporting shoulders, that are arranged perpendicular to each other to form a rectangular pattern. After the grid is installed, the tile panels are placed onto the supporting shoulders of the runners and cross-tees. Such a grid system offers many advantages such as increasing a room's energy efficiency, improving a room's acoustics, enhancing the aesthetic value of a room, lowering a ceiling, and allowing for the installation of electrical fixtures, pipes and duct work.
Ceiling grid systems are relatively inexpensive to install as compared to a plaster ceiling. As a consequence, there is a continuing need to improve on the design and integrity of grid systems, particularly in light of the fact that many such systems are installed in commercial buildings requiring years of service, or installed by the do-it-yourself home owner.
In particular, there is a need to simplify installation of ceiling grid systems. There is also a need to facilitate installation of ceiling grid systems in a low-clearance-spaced-relation to a ceiling. In many instances where a room may have a low ceiling, the ceiling grid system may need to be suspended in a closely-spaced relation to the ceiling. This limits the amount of working space above the grid in which to install the ceiling grid system, and more particularly, ceiling tiles. Many current ceiling grid systems are difficult or impossible to install in such low clearance spaces because the cross-tees are typically connected to the main-runners by tilting the rear end of the cross-tee upward and the front end of the cross-tee downward. This installation is extremely difficult in low clearance spaces because the ceiling prevents the rear end of the cross-tee from being tilted upward. In addition, installation is difficult because there is little room to install the ceiling tiles above the ceiling grid system because of the low clearance.
There is a further need to extend the life of the ceiling grid system. After a period of use, a suspended ceiling grid system (e.g. one made from metal) may begin to degrade. More particularly, metal components that have been painted may start to rust, flake, chip, or even become damaged by denting. Further, the color of a painted metal grid system as seen by a room's occupant may become discolored or faded over time. For example, in a food processing plant, flaking paint from a suspended ceiling grid system may be a safety and/or health hazard. In general, such degraded ceiling grid systems are not aesthetically pleasing. Typically, such a degraded ceiling grid system has to be either repainted or removed/replaced with a new ceiling grid system, both at a high cost in labor and materials. Repainting may also be a temporary fix in that it is likely the paint will begin to flake or peel again. In addition, chemicals emitted in certain factories and plants may also be harmful to the ceiling grid system. As a result, these grid systems need to be replaced